The IBM first couples the membrane to the fluid via an interpolation of the nodal forces of the 3D triangular mesh on the lattice sites; then, interpolating the fluid velocity on the mesh nodes we get the coupling between the fluid and membrane [1]}. The interpolation is performed by means of discrete Delta functions (in particular, we use a 4-point stencil). For more details on the model adopted, we refer to our previous work [2]}.
